HEAT TREATMENT SERVICES
This Division handles the specialized fields of Post Weld Heat Treatment (PWHT), stress relieving and Pre Heating services to meet the onsite requirements of Oil & Gas, Refinery and Petrochemical industries. The division also handles the rental and sales of equipment & consumables as well as providing calibration services. The team had established its reputation in high quality workmanship and on time project execution and have a strong presence in such services. Our specialized heat treatment services include
Post Weld Heat Treatment, Pre-heating, Post-heating, Annealing & Normalizing, Refractory Dryouts / Paint Curing, De-Chocking of piping and equipments (i.e Polimer, Polyethylene etc...), Furnace firing (Electrical/Fuel burners), Hardness Testing, Equipment & consumables sales and rental, Repair & calibration of equipment.
- Heat Treatment
Heat treatment is the controlled heating and cooling of metals. Steels are treated for softening/Hardening/Material Modification.
- Post Weld Heat Treatment(PWHT)
Heat Treatment of the welded joint, normally to sub-critical temperatures after completion of welding operations.
• Electrical Resistance Method
• Furnace or Internal firing
• Stress Relaxation
• Tempering
• Hydrogen Removal
• Improvement in material’s hardness
• Toughness and metallurgical properties of the weld
- Pre-heating
Heating of the base metal at the area to be welded. Reasons:
• To avoid HAZ (Heat affected Zone) / weld metal cold cracking
• To minimize residual stress
• To provide sufficient ductility in the weld metal and HAZ
- Annealing/Normalizing
To bring back the base metal weldability.
• Heat to a temperature 40 – 50 0 C above the upper critical point.
• Soak for sufficient length of time.
• Annealing: Cooling very slowly (Furnace Cooling)
• Normalizing: Cooling in air
• To improve mechanical properties
• Tensile strength, impact value
• In turn, better resistance to brittle fracture (improved ductility)
• To refine Grain Size
• To relieve internal stresses
- Solution Annealing
Solution annealing is a high temperature heat treating process performed on steels, here austenitic Steel is heated to above 1050°C followed by Soaking and Quenching. Reasons:
• To Soften the material.
• Remove carbide precipitation formed at grain boundaries during manufacturing process.
• To improve corrosion resistance.
- Dehydrogenation Heat Treatment
Dehydrogenation Heat treatment is performed to remove hydrogen from material prior to manufacture, fabrication or repair activity. DHT / HBO of the component is normally heated to 350⁰C / 400⁰C for 4 hours holding period.
- Hardness Testing
Hardness is the property of a material that enables it to resist plastic deformation, usually by penetration. However, the term hardness may also refer to resistance to bending, scratching, abrasion or cutting.
• Brinell Hardness Test: A comparison indention hardness test using calibrated machine/equipment, into the material under test and measuring the impression diameter and comparing with a measurement in a known BHN test bar.
